Need help with High RPM Miss
#1
Need help with High RPM Miss
ok the first part of this year I just assumed this was valve float, but after a spring/cam/lifter swap, I'm still getting the miss.
My old cam should have pulled to atleast 6800 rpms, and this one should pull to well over 7200.. (Solid Roller).
Ok with the cam swap, I also changed the spark plugs, spark plug wires, and the coil.
I've tested the car at the track with and with out the MSD 6al hooked up.. still happens.
The Opti spark is new and only has like 500-600 miles on it.
What else could it be?
<<also, dumb me broke the wire on my knock sensor, and managed to forget about it and thought it was a ground wire so grounded it what do you think this is telling the computer?>>
Thanks in advance, I'd really like to figure out whats going on with the car, I'm suppose to go to the track next friday and from inital runs on it, it sure doesn't feel like a high 10 second car.
Jason
My old cam should have pulled to atleast 6800 rpms, and this one should pull to well over 7200.. (Solid Roller).
Ok with the cam swap, I also changed the spark plugs, spark plug wires, and the coil.
I've tested the car at the track with and with out the MSD 6al hooked up.. still happens.
The Opti spark is new and only has like 500-600 miles on it.
What else could it be?
<<also, dumb me broke the wire on my knock sensor, and managed to forget about it and thought it was a ground wire so grounded it what do you think this is telling the computer?>>
Thanks in advance, I'd really like to figure out whats going on with the car, I'm suppose to go to the track next friday and from inital runs on it, it sure doesn't feel like a high 10 second car.
Jason
#3
Go back to the stock one? I had a MSD one on there that the end broke on and replaced it with a new MSD one today. So would mean both MSD coils were bad. But wouldn't supprise me I guess.
Thanks,
Jason
Thanks,
Jason
#4
Well, as many in my situation, I reviewed all the old posts on this same topic and no real solutions.
I guess a couple things I can try:
New fuel filter(mine is only 3 years 2kmiles old, but worth a shot)
and MAF....
This is really frustrating, and even more so seeing so many people with the same problem and no real answer
Any help here would be MUCH appreicated!!
Thanks,
Jason
I guess a couple things I can try:
New fuel filter(mine is only 3 years 2kmiles old, but worth a shot)
and MAF....
This is really frustrating, and even more so seeing so many people with the same problem and no real answer
Any help here would be MUCH appreicated!!
Thanks,
Jason
#5
Im having the same problem and Im hoping its the coil. How specific is the miss? Mine always seems to happen in the 5500-6000 rpm range all the time. I did just change the fuel filter and my MAF is working fine AFAIK.
#6
It's pretty consistantly hitting at 6200rpms. But I pulled the car out of my drive way drove it .5 miles down the road and floored it and it didn't hit until 6800rpms.
I haven't gotten a chance to check fuel pressure, I'm kinda leaning towards that I guess. But just have a hard time believing it because I have a new stock fuel pump (5k miles, 3 years old) and a NOS inline fuel pump(5kmiles, 3 years old).. But maybe.
Jason
I haven't gotten a chance to check fuel pressure, I'm kinda leaning towards that I guess. But just have a hard time believing it because I have a new stock fuel pump (5k miles, 3 years old) and a NOS inline fuel pump(5kmiles, 3 years old).. But maybe.
Jason
#7
I have a Walbor 255 intake so that shouldnt be a problem for me. I still have to take the valvecovers off but it sounds like I may have a couple rockers loose. Not sure if thatll cause a specific miss though.
#8
this may sound dumb...but get a can of brake cleaner/carb cleaner, and start spraying around your intake and all the vacuum hoses...mine had this high rpm miss also like from 5000-6200 and it kept me wonderin what it was...mine turned out to be a small rubber elbow that connects a little black box located above the passenger side exhaust manifold, about mid-way of the intake... it has two plastic lines coming out of it, and a plug-in-connector...i have no clue what it is or does, but i replaced the dry-rotted rubber elbow, and my car runs like a scalded ape!!!
all in all just check for vacuum leaks, i also changed my gas cap at this time too, start with the simple stuff first! also the coil wire its self might be a prob. too.
just my opinions,
steve
all in all just check for vacuum leaks, i also changed my gas cap at this time too, start with the simple stuff first! also the coil wire its self might be a prob. too.
just my opinions,
steve
#10
Originally posted by whitedakota
this may sound dumb...but get a can of brake cleaner/carb cleaner, and start spraying around your intake and all the vacuum hoses...mine had this high rpm miss also like from 5000-6200 and it kept me wonderin what it was...mine turned out to be a small rubber elbow that connects a little black box located above the passenger side exhaust manifold, about mid-way of the intake... it has two plastic lines coming out of it, and a plug-in-connector...i have no clue what it is or does, but i replaced the dry-rotted rubber elbow, and my car runs like a scalded ape!!!
all in all just check for vacuum leaks, i also changed my gas cap at this time too, start with the simple stuff first! also the coil wire its self might be a prob. too.
just my opinions,
steve
this may sound dumb...but get a can of brake cleaner/carb cleaner, and start spraying around your intake and all the vacuum hoses...mine had this high rpm miss also like from 5000-6200 and it kept me wonderin what it was...mine turned out to be a small rubber elbow that connects a little black box located above the passenger side exhaust manifold, about mid-way of the intake... it has two plastic lines coming out of it, and a plug-in-connector...i have no clue what it is or does, but i replaced the dry-rotted rubber elbow, and my car runs like a scalded ape!!!
all in all just check for vacuum leaks, i also changed my gas cap at this time too, start with the simple stuff first! also the coil wire its self might be a prob. too.
just my opinions,
steve
#11
well I can confirm that my vacum lines are jacked up, one is broke, and one keeps sliping off. If thats my problem lol, I think I'll smack myself. I guess i just didn't think a small vacum leak would matter. I'll that tomorrow and see if it fixes the problem.
Thanks,
Jason
Thanks,
Jason
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